JP2667992B2 - Flash photography switching device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a camera having a lens shutter and a focal plane shutter.

(Prior art and its problems) Cameras equipped with a lens shutter (hereinafter referred to as LS) (hereinafter referred to as LS camera) and cameras equipped with a focal plane shutter (hereinafter referred to as FPS) (hereinafter referred to as FPS)
Cameras) are all well known.

The LS camera is effective for flash photography due to the feature of the shutter opening mode, while the FPS camera is capable of changing lenses from the flash mode and controlling time at high speed from the operation mode.

In order to make use of the features of the above two types of cameras, there has been proposed an interchangeable lens of a type having an LS that operates independently in an interchangeable lens of an FPS camera.

However, since it is a shutter that operates independently as an interchangeable lens, and the control part is individually provided in the FPS and the LS, there are many useless parts.

In order to solve the above problem, the same applicant has already proposed a camera system including LS and FPS. (Japanese Patent Application 63
However, there still remains a problem to be solved as a camera that fully utilizes an LS effective for flash photography.

(Object of the Invention) The present invention has been made in view of the above problems,
An object of the present invention is to provide a camera that includes an LPS and automatically selects an LS mode for a subject on which flash photography is to be performed, thereby preventing photographing errors.

(Means for Achieving the Object) According to the present invention, in a camera including a lens shutter for performing a program exposure operation and an aperture adjustment operation and a focal plane shutter, a lens shutter mode in which the lens shutter operates as a program shutter, Switching means for setting a focal plane shutter mode for controlling a shutter speed by a focal plane shutter and controlling an aperture by the lens shutter; first driving means for controlling a program exposure value and / or an aperture value of the lens shutter; Second drive means for controlling the operation time of the focal plane shutter, sequence control means for controlling the operation timing of the two drive means, and setting means for selecting and setting automatic exposure by natural light and automatic exposure by flash light When The above object is achieved by a flash photography switching device comprising: a forced switching means for setting a lens shutter mode regardless of the setting of the switching means when the setting means is set to automatic exposure by flash.

(Configuration) Referring to the drawings showing an embodiment of the present invention, in detail, in FIG. 1, a photographing lens 2 is mounted on a camera body 1 while being supported by a lens barrel 3. The subject image passing through the lens 2 forms an image on a photosensitive material F (hereinafter, referred to as a film) stored behind a range limited by the photographing screen 4.

A finder 5 having a field frame at the top of the camera body;
There is provided a light-shielding tube 6 for blocking harmful light from a portion other than the taking lens to the film, and a release button 7 for operating the camera is provided on the upper surface of the camera.

A lens shutter (LS) 8 for opening and closing the lens opening is provided behind the taking lens 2, and the lens opening is normally closed by shutter blades 8a.

The stepping motor 9 is a shutter blade that is disposed in the lens barrel 3 and also serves as an aperture according to an output signal of the first driving unit D1.
8a opens and closes.

An electronic circuit 10 for controlling the step motor 9 includes a first drive unit D1, a sequence control unit SC for controlling the operation timing of each shutter, a photometric circuit including a light receiving element for photometric luminance of the subject, and a second It comprises driving means and the like.

The focal plane shutter (FPS) 11 has a structure in which a front curtain 13 and a rear curtain 14 are supported on a substrate 12 attached to the camera body 1, and two electromagnets (not shown) are driven by a second driving unit D2 of the electronic circuit 10. Are operated at desired time intervals to control the exposure time.

The FPS 11 is charged by a known method at the time of film feeding, and when performing a multiple exposure operation, the FPS 11 is separated from the film feeding and charged alone.

Switching means 15 is provided at the top of the camera to select whether to perform photographing using FPS11 or LS8.

Also, a setting means 16 for selecting and setting automatic exposure by natural light and automatic exposure by flash light is provided on the upper part of the camera.

FIG. 2 is a block diagram showing an operation system having the above configuration.

The calculating means 105 includes a photometric circuit 101 including a light receiving element for measuring the brightness of the subject, a distance measuring circuit 102 for measuring a distance to the subject, a means 20 for setting a focal length f of the photographing lens 2, and a film sensitivity setting. The signal is output to the switching means 15 and a sequence control means SC described later, using the signal of the means 104 for performing the input as an input.

The switching means 15 selects whether to perform the program exposure operation by the LS or the exposure time control by the FPS. In other words, once you press the part protruding above the camera, LS
Is set to the lens shutter mode in which is operated, and when pressed again, the focal plane shutter mode in which the FPS is operated is set, and when pressed again, the lens returns to the lens shutter mode.

Even if the setting means 16 is set to the position of automatic exposure by natural light, when the output Q1 of the calculating means 105 indicates that the situation of the subject can no longer be automatically exposed by natural light, the forced switching means 107 The lens shutter mode is forcibly set.

The output Q2 of the arithmetic means 105 outputs a signal corresponding to each mode to the sequence control means SC in order to set an exposure level according to the brightness of the subject.

The mode display means 106 displays which setting mode is set, and when the lens shutter mode is forcibly set, the mode is displayed repeatedly by blinking.

Based on a signal from the switching means 15 or the forcible switching means 107, the sequence control circuit SC switches the first driving means D1 and the second driving means
The operation sequence with D2 is set at a preset timing, FPS11
And activate the LS8.

Next, the operation method will be described with reference to FIGS. 4 and 5, the horizontal axis represents the elapsed time and the vertical axis represents the exposure amount or the screen position on the photographing screen 4.

In the operation flowchart of FIG. 3, step # 1
Indicates a state in which the release button 7 of the camera is depressed and power is supplied to the entire camera device from a power supply (not shown).

The steps will be described below. In step # 2, the information SV from the film sensitivity setting means 104 is changed to step # 2.
In step 3, the information BV from the photometry circuit 101 is further added to the step
In step 4, the information DV from the distance measuring circuit 102 is input to the arithmetic circuit 105, and the arithmetic operation is performed in step # 5. In step # 6, the information GV from the flash device 17, the information ZV from the focal length setting means 104, and the above information DV are input to the arithmetic circuit 105 for calculation, and the calculation in step # 7 is performed.

In step # 8, the setting means 16 sets the flash device 17
It is determined whether or not the flash mode has been set, and if the shooting mode is set in the natural light state, the process proceeds to step # 9.

In step # 9, it is determined whether or not the flash device 17 should automatically emit light based on the above calculation result. Done.

If it is determined in step # 9 that automatic light emission is required, the process proceeds to step # 11, where it is determined whether or not the switching means 15 is set to the LS mode. Therefore, if the LS mode is set, the fourth step is performed in the order of steps # 12, # 13, and # 14.
The exposure operation is performed in the sequence shown in FIG. The flash device 17 emits light in a known manner according to the signal of the LS.

On the other hand, in step # 11, if the FPS mode has been set, the process proceeds to step # 15, where it is determined whether the shutter speed at which the FPS11 should operate is shorter than the time required to synchronize with the flash of the flash device on the full screen, and If step # 12 or later is performed, move to step 16 # where FPS11
At the shutter speed to be operated, it is determined whether or not camera shake occurs during photographing. If camera shake occurs, the process proceeds to step # 12, and the subsequent LS operation is performed. If there is no risk of camera shake, the process proceeds to step # 17, and in the sequence shown in FIG.
Thus, a predetermined aperture diameter d1 is set. Subsequently, in step # 19, the front curtain 13 of the FPS 11 opens, in step # 20, the flash device 17 emits light, and further, in step # 21, the rear curtain
14 runs and finishes exposure.

Also, in step # 8, the setting means 16
If the flash mode using 17 is set, the process proceeds to step # 11, and thereafter, steps # 11 and # 11 are performed in the same manner as described above.
A determination is made in steps 15 and 16, and if the operation should be performed by LS8, the process proceeds to step # 12. If the operation is to be performed by FPS11, the process proceeds to step # 18.
Operates.

FIG. 4 is an operation diagram when the switching means 15 is set to the lens shutter mode in which the exposure operation is performed by the LS8. When the release button 7 in FIG. 1 is pressed during photographing, the sequence control means SC first specifies the second driving means D2 to output a signal, and the front curtain 13 of the FPS 11 is moved to one end P of the screen.
The photographing screen 4 is opened by operating from 1 to the other end P2.

Next, the sequence control means SC designates the first drive means D1 to output a signal to open / close the LS8 to expose the film F with the light quantity corresponding to the area Q1. At this time, the LS 8 performs a program exposure operation combining the aperture and time depending on the brightness of the subject.

Subsequently, the sequence control means SC designates the second driving means D2 to output a signal, activates the rear curtain 14 of the FPS 11 from one end P1 to the other end P2, and closes the photographing screen 4.

When the operation of FPS11 ends, the sequence control means SC
A signal for winding the film F up to the new frame number is output, and a motor (not shown) is operated to charge the FPS 11.

With the above operation, the photographing in the lens shutter mode is completed.

FIG. 5 is an operation diagram when the switching means 15 is set to a focal plane shutter mode in which the FPS 11 performs an exposure operation.

When the release button 7 in FIG. 1 is pressed during photographing, the sequence control means SC first specifies the first driving means D1 to output a signal, and opens the LS8 to a predetermined aperture value d1, Open the lens opening.

Next, the sequence control means SC designates the second driving means D2 to output a signal, and sequentially operates the front curtain 13 and the rear curtain 14 of the FPS 11 to expose the film F. At this time, the front curtain 13 and the rear curtain 14 have an aperture value d of LS8 depending on the brightness of the subject.
It operates at a time interval t that gives an appropriate exposure amount in combination with 1.

Subsequently, the sequence control means SC designates the first drive means D1 to output a signal, and closes LS8.

When the operation of the LS8 is completed, the sequence control means SC outputs a signal for winding the film F to a new number of frames, and operates a motor (not shown) to charge the FPS11.

The exposure time by PFS11 is relatively long, so-called F
As shown in FIG. 6, the operation of the PS in the flash synchronization limit speed range is a state in which the front curtain 13 is opened, the flash trigger switch is turned on at the point X, and the screen is completely opened from the position P1 to the position P2. Causes the flash device 17 to emit light.

With the above operation, the photographing in the focal plane shutter mode is completed.

In the above embodiment, the setting means 16 allows the user to set an operation unit formed outside the camera, attaches the flash device 17 to the camera, or sets the flash device built in the camera to a use state, or It is possible to automatically detect the brightness of the subject or the backlit state and perform the automatic exposure operation by the flash device.

Also, a single-lens reflex camera can be configured based on the concept of the present invention.

(Effects) As is clear from the above description, one switching unit 15 determines whether the LS or the FPS is operated, and sets the camera to the setting unit 16 so that the flash unit 17 is required.
When the FPS11 or LS8 is activated, the sequence control circuit SC performs the correct shooting at the appropriate timing even when either the FPS11 or LS8 is activated.
Is activated, and the characteristics of the two shutters can be effectively used according to the purpose of photographing.

[Brief description of the drawings]

1 shows an embodiment of the present invention. FIG. 1 is a sectional view of a camera, FIG. 2 is a block diagram showing an operation system of the camera, and FIG.
(A) and (b) are flowcharts of the camera, FIG.
5 and 6 show the operation diagram. DESCRIPTION OF SYMBOLS 1 ... Camera body 2 ... Shooting lens 5 ... Finder 7 ... Release button 8 ... Lens shutter 11 ... Focal plane shutter 15 ... Switching means 16 ... Setting means 17 ... Flash device 20 ... Focal length Setting means 105 Calculation means 107 Forced switching means SC Sequence control means D1 First driving means D2 Second driving means

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroto Tsukiki 934-13, Kadawa, Yotsukaido-shi, Chiba Inside the Seikosha Chiba Works Co., Ltd. Inside Chiba Works (72) Inventor Kanji Ito 934-13, Kadato, Yokkaido, Chiba Prefecture Seikosha Chiba Works (72) Inventor Takayuki Sato 934-13, Kadawa, Yotsukaido City, Chiba Japan Seikosha Chiba Works ( 72) Inventor Takuhito Otora 934-13 Shiwatari, Yokkaido, Chiba Pref. In Seikosha Chiba Works (72) Inventor Akiyo Hayakawa 934-13, Shikato, Yotsukaido, Chiba Pref.Sekiko Chiba Works (56) References JP-A-52-98520 (JP, A) JP-A-52-148118 (JP, A) JP-A-47-37930 (JP, A) 40464 (JP, A) JitsuHiraku Akira 55-164622 (JP, U)

Claims (1)

(57) [Claims] 1. A camera provided with a lens shutter for performing a program exposure operation and an aperture adjustment operation and a focal plane shutter, wherein a lens shutter mode in which the lens shutter operates as a program shutter, and a shutter speed is controlled by the focal plane shutter. Switching means for setting a focal plane shutter mode for controlling an aperture by the lens shutter; first driving means for controlling a program exposure value and / or an aperture value of the lens shutter; and controlling an operation time of the focal plane shutter. A second driving unit, a sequence control unit for controlling operation timings of the two driving units, a setting unit for selecting and setting an automatic exposure by natural light and an automatic exposure by a flash, and the setting unit using a flash. When set to auto exposure,
A flash photography switching device comprising: a forced switching device for setting a lens shutter mode regardless of the setting of the switching device.